East German Pat. No. 128,901 describes an intake reel for a self-powered agricultural machine which is designed to pick up cut crop, such as alfalfa, lying strewn carpet-fashion on the ground. The machine clears a wide swathe ahead of itself, picking up the crop and passing it up and back to a side feeder which conveys it off to the side to, for example, a baler. The reel has two independent halves that are separately guided relative to the ground along with support structure for strippers that pull the picked-up crop off the tines of the reel. As a result of the bulkiness and mass of these systems they do not follow the contours very responsively or sensitively. Hence it is necessary to set them a little high so some crop is not picked up, an obvious waste. In addition the picked up crop is inefficiently passed to the side feeder so that it occasionally jams up, making a blockage that must be cleared before the machine can go on.
In addition German utility model No. 8,000,724 describes a reel wherein the tines are mounted on respective rods that extend parallel to the reel axis which is horizontal and perpendicular to the machine travel direction. These rods can be pivoted about their own axes by means of of crank and cam arrangements which twist the tine-carrying rods as they orbit about the reel axis so that the tines are extended fully as they sweep forward across the ground against the travel direction and up, but so that they pivot in and shed crop on the tops of the strippers, whence it is easily transmitted to the side feeder. Separate cranks and cams are provided at both ends of the reel so that the considerable torsion exerted by the tines need not be transmitted the full length of their rods. The rods are not axially throughgoing, but instead only extend from a center plate to a respective end plate. At the center plate the rods angularly alternate to prevent overload of the drive motor for the reel.
Other arrangements, such as described in East German Pat. No. 143,496,are frequently quite complex, and not usable in any situations where the ground from which the crop is being picked up is not fairly level. Those machines capable of working in irregular terrain are invariably relatively short so they are not efficient.